Application of hairless mouse strain to bioluminescence imaging of Arc expression in mouse brain. Issue 1 (December 2017) - Izumi, Hironori
Abstract Background Bioluminescence imaging (BLI) is a powerful technique for monitoring the temporal and spatial dynamics of gene expression in the mouse brain. However, the black fur, skin pigmentation and hair regrowth after depilation of mouse interfere with BLI during developmental and daily examination. The aim of this study was to extend the application ofArc -Luc transgenic (Tg) mice to the BLI of neuronal activity in the mouse brain by introducing the hairless (HL) gene and to examineArc -Luc expression at various developmental stages without interference from black fur, skin pigmentation, and hair regrowth. Results TheArc -Luc Tg HL mice were established by crossing the Tg C57BL/6 mouse strain with the HL mouse strain. Under physiological and pathological conditions, BLI was performed to detect the signal intensity changes at various developmental stages and at an interval of <7 days. The establishedArc -Luc Tg HL mice exhibited clear and stable photon signals from the brain without interference during development. After surgical monocular deprivation during visual-critical period, large signal intensity changes in bioluminescence were observed in the mouse visual cortex. Exposure of mice to a novel object changed the photon distribution in the caudal and rostral cerebral areas. The temporal pattern of kainic-acid-inducedArc -Luc expression showed biphasic changes in signal intensity over 24 h. Conclusions This study showed the advantages of using the mutant HL gene in BLI ofArc expression in the mouse brain at various developmental stages. Thus, the use of theArc -Luc Tg HL mice enabled the tracking of neuronal-activity-dependent processes over a wide range from a focal area to the entire brain area with various time windows.